Washing machine

ABSTRACT

A washing machine including a dissolving unit and a bubble generating unit. The dissolving unit includes a hollow outer body that has an open end, and a hollow inner body that has an open end. The inner body is disposed in the outer body. The gap between the inner and the outer body forms a dissolving flow path. A dissolving cap is coupled to one side of the outer body to retain air in the outer body and the inner body. A dissolving inlet port is formed to receive water supplied from the outside to the inner body. A control unit controls the water supply unit and the drain valve so as to stop an inflow of the water/air mixture to be supplied into the bubble generating unit.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims benefit and priority to Korean Patent Application No. 10-2016-0124311, filed on Sep. 27, 2016, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference for all purposes.

TECHNICAL FIELD

Embodiments of the present disclosure relate to washing machines, and more particularly, to mechanisms that facilitate removal of residual detergent on laundry.

BACKGROUND OF THE INVENTION

Generally, a washing machine washes laundry by friction made between water and the laundry when a pulsator rotates in the drum of the washing machine. Holes in the drum allow water to flow between the tub and the drum. During a washing, rinsing, or spin-drying process, water can be discharged out of the tub through a drain line, e.g., installed at a lower side of the tub.

After processing the laundry, there may be residual detergent or other foreign substances remaining on the washed clothes, which may cause irritating skin condition of a person wearing the clothes, for example atopic dermatitis.

Various technologies have been developed to solve this problem, typically by supplying a concentrated water flow to the laundry clothes, where the flow is generated by a separate device, such as a pump. Unfortunately, the operation of such a pump produces unwanted noise, and it is difficult to perform maintenance on the pump after the pump is repeatedly used.

SUMMARY OF THE INVENTION

Embodiments of the present disclosure provide a washing machine operable to generate and supply bubbles to facilitate removal of residual detergent and foreign substances adherent to laundry and thereby enhance cleaning effectiveness.

An exemplary embodiment of the present disclosure provides a washing machine including: a water supply unit which supplies washing water; a dissolving unit which stores air therein, and mixes water supplied from the water supply unit with inside air so that the stored air is dissolved in the supplied water; a bubble generating unit which generates bubbles by using the water with dissolved air introduced from the dissolving unit; a drain valve which is installed in the dissolving unit and discharges the water mixed with air remaining in the dissolving unit to the outside of the dissolving unit; and a control unit which controls the water supply unit and the drain valve to stop an inflow of the water with dissolved air to be supplied into the bubble generating unit.

The washing machine may further include a water level sensor which is installed in the dissolving unit, detects a level of water in the dissolving unit, and provides the detected information to the control unit.

When the information detected by the water level sensor is equal to or higher than a preset first water level information value, the control unit may stop the supply of the washing water from the water supply unit and open the drain valve.

When the information detected by the water level sensor is lower than a preset second water level information value after the drain valve is opened, the control unit may close the drain valve.

The control unit may close the drain valve when a preset time has elapsed after the drain valve has been opened.

The dissolving unit may include: an outer body which is opened at one side and has a hollow interior; an inner body which is opened at one side, and disposed in the outer body such that an outer circumferential surface of the inner body is spaced apart from an inner circumferential surface of the outer body to form a dissolving flow path; a dissolving cap which is coupled to one side of the outer body, and has a dissolving inlet port formed such that the water supplied from the outside is supplied into the inner body; a porous portion which is formed in one area of the inner body; a dissolving guide port which is formed in the outer body, and guides the water passing through the dissolving flow path to the bubble generating unit; and a dissolving drain port which is formed in the outer body to be spaced apart from the dissolving guide port and in which the drain valve is installed.

The dissolving unit may further include an inner hole which is formed at the other side of the inner body and communicates with the dissolving flow path.

The dissolving unit may further include an air supply check valve which is installed in the dissolving cap, and opened when the water is discharged through the dissolving drain port, such that air is introduced into the outer body and the inner body.

The washing machine may further include: a housing; a tub which is installed in the housing and into which the bubbles generated by the bubble generating unit are supplied; and a drum which is installed in the tub and accommodates laundry.

The dissolving unit may be disposed between the housing and the tub, and disposed to be closer to a lower side of the tub than an upper side of the tub.

Another exemplary embodiment of the present disclosure provides a washing machine including: a housing; a tub which is installed in the housing; a drum which is disposed inside the tub and accommodates laundry; a water supply unit which supplies washing water; a dissolving unit which stores air therein, and mixes water supplied from the water supply unit with inside air so that the stored air is dissolved in the supplied water; a bubble generating unit which generates bubbles by using the water with dissolved air supplied from the dissolving unit, and supplies the bubbles into the tub; a drain valve which is installed in the dissolving unit and discharges the water mixed with air remaining in the dissolving unit to the outside of the dissolving unit; and a control unit which cuts off the supply of the washing water to be supplied into the dissolving unit by controlling the water supply unit and controls and opens the drain valve to discharge the water mixed with air remaining in the dissolving unit to the outside of the dissolving unit when the bubbles stop being supplied into the tub.

When the control unit determines that the water mixed with air remaining in the dissolving unit has been completely discharged, the control unit may close the drain valve.

According to the exemplary embodiments of the present disclosure, the washing machine can advantageously generate bubbles and use the bubbles to enhance cleaning performance, because the bubbles can decrease surface tension between laundry and residual detergent or foreign substances remaining on the laundry.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the configuration of an exemplary washing machine according to an embodiment of the present disclosure.

FIG. 2 is a perspective view illustrating an exemplary dissolving unit and a tub in FIG. 1.

FIG. 3 illustrates an exemplary configuration of a control device of the washing machine of the present disclosure.

FIG. 4 is a view illustrating cross sections of the dissolving unit and a bubble generating unit in FIG. 1.

FIG. 5 is an exploded perspective view of the dissolving unit in FIG. 1.

DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here.

Hereinafter, an exemplary embodiment of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the technical field to which the present disclosure pertains may easily carry out the exemplary embodiment. The present disclosure may be implemented in various different ways, and is not limited to the exemplary embodiments described herein.

It is noted that the drawings are illustrative, and are not illustrated based on actual scale. Relative dimensions and proportions of parts illustrated in the drawings are exaggerated or reduced in size for the purpose of clarity and convenience in the drawings, and any dimension is merely illustrative and not restrictive. The same reference numerals designate the same structures, elements or components illustrated in two or more drawings in order to exhibit similar characteristics.

Exemplary drawings of the present disclosure illustrate exemplary embodiments of the present disclosure in more detail. As a result, various modifications of the drawings are expected. Therefore, the exemplary embodiments are not limited to specific forms in regions illustrated in the drawings, and for example, include modifications of form by manufacture.

Hereinafter, a washing machine 101 according to the exemplary embodiment of the present disclosure will be described with reference to FIGS. 1 to 5.

As illustrated in FIGS. 1 to 3, the washing machine 101 includes a water supply unit 130, a dissolving unit 300, a bubble generating unit 400, a drain valve 900, and a control unit 700.

The water supply unit 130 can supply washing water from an external washing water supply source, or may draw washing water that has already been supplied in the washing machine 101.

Air can be stored in the dissolving unit 300. Water is supplied into the dissolving unit 300 from the water supply unit 130. Water supplied into the dissolving unit 300 can be mixed with (or dissolve) air in the dissolving unit 300.

More specifically, the washing machine 101 includes a housing 100, a tub 200, a drum 250, a pulsator 260, and a drive unit 270.

The housing 100 defines an exterior of the washing machine 101. The tub 200 is disposed in the housing 100 and can store washing water. The drum 250 is disposed in the tub 200 and can accommodate laundry. The pulsator 260 is disposed at a lower side of an interior of the drum 250 and can generate a water flow in the drum 250. The drive unit 270 is installed at a lower side of the housing 100 and provides rotational force to the pulsator 260 and the drum 250.

As illustrated in FIG. 1, the dissolving unit 300 is disposed between the tub 200 and the housing 100. More specifically, the dissolving unit 300 is disposed closer to a lower side of the tub 200 than an upper side of the tub 200. In this configuration, the dissolving unit 300 may be effectively installed without limitations imposed by the installation positions of the housing 100 and the tub 200 even though the housing 100 and the upper side of the tub 200 are supported by a suspension system. In other words, since the dissolving unit 300 is disposed closer to the lower side of the tub 200 than the upper side of the tub 200, the dissolving unit 300 may be conveniently installed despite the narrow space between the housing 100 and the tub 200.

The bubble generating unit 400 can generate bubbles from the water/air mixture supplied from the dissolving unit 300. More specifically, as illustrated in FIG. 4, the bubble generating unit 400 may include: a bubble body 410 which includes a bubble inlet port 411 at a first side of the bubble body 410 and a bubble discharge port 412 at a second side of the bubble body 410; a bubble nozzle 420 which is disposed in the bubble body 410 and has a bubble flow path 421 that has an inner diameter increasing from the bubble inlet port 411 to the bubble discharge port 412 and can generate bubbles; a pressure reduction region 440 which is disposed between the bubble nozzle 420 and the bubble discharge port 412 and can reduce pressure of the bubbles that have passed through the bubble nozzle 420; and a bubble check valve 430 which is disposed between the bubble inlet port 411 and the bubble nozzle 420 and guides the water with dissolved air introduced from the bubble inlet port 411 to the bubble nozzle 420.

A water level sensor 190 can detect an amount of (or a surface level) of water in the dissolving unit 300. The water level sensor 190 may be installed in the dissolving unit 300.

The drain valve 900 may discharge the water/air mixture from the dissolving unit 300 out of the dissolving unit 300. The drain valve 900 may be installed in the dissolving unit 300. More specifically, the drain valve 900 may discharge any remaining water/air mixture that has not been supplied to the bubble generating unit 400 out of the dissolving unit 300.

For example, the drain valve 900 may discharge the water/air mixture remaining in the dissolving unit 300 to a drain line 210 installed at the lower side of the tub 200 that stores the washing water. Alternatively, the drain valve 900 may be installed in a pipe that couples between the dissolving unit 300 and the drain line 210.

Based on the information detected by the water level sensor 190, the control unit 700 can determine a bubble generation state of the bubble generating unit 400. More specifically, based on the detected level of water (e.g., height of the water surface) in the dissolving unit 300, the control unit 700 may calculate the amount of air stored in the dissolving unit 300. Further, the control unit 700 may determine whether the amount of air in the dissolving unit 300 may be effectively dissolved in the supplied water and whether the bubble generating unit 400 may effectively generate bubbles.

The control unit 700 can selectively control the drain valve 900 and the water supply unit 130. As an example, the drain valve 900 may be any of the various types of valves that are well known in the art, such as an electronic control valve, a solenoid valve, and an opening and closing valve. The drain valve is controlled by the control unit 700. The drain valve may allow the water/air mixture remaining in the dissolving unit 300 to be discharged.

Therefore, the control unit 700 may control the amount of air in the dissolving unit 300 to allow the bubble generating unit 400 to effectively generate bubbles.

The control unit 700 may stop a supply of the washing water from the water supply unit 130 when the information detected by the water level sensor 190 is equal to or higher than a preset first water level information value. In this case, the control unit 700 may open the drain valve 900.

The first water level information value may be preset in the control unit 700. When a level of water in the dissolving unit 300 as detected by the water level sensor 190 is equal to or higher than this value, the control unit 700 may determine that the stored air cannot be effectively dissolved in the supplied water because the ratio between the amount of air currently contained in the dissolving unit 300 and the amount of water being currently supplied into the dissolving unit 300 is smaller than a predetermined ratio. In some embodiment, this ratio is 1.

That is, when a level of water in the dissolving unit 300 as detected by the water level sensor 190 is equal to or greater than the first water level information value, the control unit 700 may determine that the interior of the dissolving unit 300 needs to be refilled with more air. Therefore, the control unit 700 stops the supply of washing water from the water supply unit 130 to the dissolving unit 300, and opens the drain valve 900. In this case, with the opened drain valve 900, water in the dissolving unit 300 is discharged from the dissolving unit 300, and no water is supplied into the bubble generating unit 400.

The control unit 700 of the washing machine 101 according to the exemplary embodiment of the present disclosure may determine whether the information detected by the water level sensor 190 is lower than a preset second water level information value.

The second water level information value may be preset in the control unit 700. The second water level information value is a value which is relatively lower than the first water level information value and using this value the control unit 700 may determine whether the water remaining in the dissolving unit 300 is discharged to the outside of the dissolving unit 300.

When the information detected by the water level sensor 190 is lower than the preset second water level information value after the drain valve 900 is opened, the control unit 700 may determine that water has been completely discharged out of the dissolving unit 300. In this case, the control unit 700 may close the drain valve 900.

Alternatively, a control unit 700 of a washing machine 101 according to another exemplary embodiment of the present disclosure may close the drain valve 900 when a preset time has elapsed after the drain valve 900 has been opened.

The time used to discharge water out of the dissolving unit 300 may be preset in the control unit 700. More specifically, the control unit 700 may control and close the drain valve 900 according to a timer, or the like, that counts time.

That is, the control unit 700 may control the closing of the drain valve 900 when the preset time has elapsed after the drain valve 900 has been opened.

As illustrated in FIGS. 4 and 5, the dissolving unit 300 of the washing machine 101 according to the exemplary embodiment of the present disclosure may include an outer body 310, an inner body 320, a dissolving cap 330, a porous portion 321, a dissolving guide port 311, and a dissolving drain port 312.

The outer body 310 may have a hollow interior. The outer body 310 is formed to be opened at one side. The other side of the outer body 310 may be formed approximately in a hemispheric shape. That is, a cross section of the outer body 310 may be formed approximately in a “U” shape.

A dissolving water supply port 331 is formed in the dissolving cap 330 such that water supplied from the water supply unit 130 can pass through the dissolving water supply port 331. The dissolving cap 330 may be formed approximately in a hemispheric shape, and the dissolving water supply port 331 may be formed on the top of the dissolving cap 330.

The dissolving cap 330 may be coupled to the open side (the first side) of the outer body 310. Therefore, air may be effectively retained in the area enclosed by the dissolving cap 330 and the outer body 310.

The inner body 320 may be open on the first side. The second side of the inner body 320 may be formed approximately in a hemispheric shape. The inner body 320 may be disposed inside the outer body 310. The gap between an outer circumferential surface of the inner body 320 and an inner circumferential surface of the outer body 310 forms a dissolving flow path for water or water/air mixture.

The open side (the first side) of the inner body 320 may be held and supported by the open side (the first side) of the outer body 310. More specifically, one end portion of the inner body 320 may be held and supported by the open side of the outer body 310. That is, one area at the first side of the inner body 320 has a larger diameter than the remaining area of the inner body 320 such that the first side of the inner body 320 may be held and supported by the open side of the outer body 310. Thus, a dissolving flow path is formed between the outer circumferential surface of the remaining area of the inner body 320 and the inner circumferential surface of the outer body 310. In other words, the open side of the outer body 310 is coupled to the dissolving cap 330, and may also support the inner body 320.

The porous portion 321 may be formed at the first side of the inner body 320. Water flows along a longitudinal direction of the inner body 320 and then overflows to the dissolving flow path through the porous portion 321. Therefore, air in the dissolving unit 300 may be mixed with the water supplied into the dissolving unit 300 through the dissolving inlet port 331 while the water flows along the inner body 320, the porous portion 321, and the dissolving flow path by water supply pressure. During the course, air may be dissolved in the water.

The dissolving guide port 311 may be disposed in the outer body 310. The dissolving guide port 311 may guide the water/air mixture in the dissolving unit 300 so that the water/air mixture is supplied into the bubble generating unit 400. More specifically, the dissolving guide port 311 may extend from the second side of the outer body 310 in a circumferential direction.

As an example, the dissolving guide port 311 is coupled to the bubble inlet port 411, and may guide the water/air mixture to enter the bubble generating unit 400.

The dissolving drain port 312 may be formed in the outer body 310. The dissolving drain port 312 may be spaced apart from the dissolving guide port 311. The drain valve 900 may be installed in the dissolving drain port 312. Therefore, the drain valve 900 may open the dissolving drain port 312 to discharge water from the dissolving unit 300 out of the dissolving unit 300.

As illustrated in FIG. 5, the dissolving unit 300 of the washing machine 101 according to the exemplary embodiment of the present disclosure may further include an inner hole 322.

The inner hole 322 may be formed at the second side of the inner body 320. More specifically, the inner hole 322 may be formed at the bottom of the hemispheric part of the inner body 320. The inner hole 322 may be small enough to prevent water that is supplied from the water supply unit 130 into the inner body 320 from being discharged directly to the dissolving flow path through the inner hole 322.

That is, when the water supply unit 130 stops the supply of water to the dissolving unit 300, the inner hole 322 can guide water in the inner body 320 to be discharged to the dissolving drain port 312 through the dissolving flow path.

The dissolving unit 300 of the washing machine 101 according to the exemplary embodiment of the present disclosure may further include an air supply check valve 340.

The air supply check valve 340 may be installed in the dissolving cap 330. The air supply check valve 340 may be selectively opened in accordance with the air pressure in the dissolving unit 300. The air supply check valve 340 may be installed in the dissolving cap 330 and spaced apart from the dissolving inlet port 331.

When water is discharged out of the dissolving unit 300 through the dissolving drain port 312, air pressure in the dissolving unit 300 may decrease. Thus the air supply check valve 340 may be opened to allow outside air to enter the dissolving unit 300.

When the air supply check valve 340 is opened to let in additional air when water is being discharged through the dissolving drain port 312, the increased air pressure can facilitate discharge of water through the dissolving drain port 312.

The air supply check valve 340 is closed when the drain valve 900 is closed to stop the discharge of water through the dissolving drain port 312. The interior of the dissolving unit 300 becomes filled with air, and then the internal pressure in the dissolving unit 300 is equal to or greater than predetermined pressure. That is, when the internal pressure in the dissolving unit 300 is equal to or higher than the predetermined pressure, the air supply check valve 340 may prevent air leakage from the dissolving unit 300.

As illustrated in FIG. 1, the washing machine 101 according to the exemplary embodiment of the present disclosure may further include the housing 100, the tub 200, and the drum 250.

The housing 100 defines an exterior of the washing machine 101. The tub 200 may contain washing water for washing laundry such as clothes or other suitable objects. The tub 200 is disposed in the housing 100.

The drum 250 can accommodate laundry such as clothes. The drum 250 is installed in the tub 200.

As illustrated in FIG. 1, the dissolving unit 300 of the washing machine 101 according to the exemplary embodiment of the present disclosure is disposed between the housing 100 and the tub 200.

The dissolving unit 300 is disposed between the tub 200 and the housing 100 which are spaced apart from each other in the housing 100. More specifically, the dissolving unit 300 is disposed proximate to the drive unit 270 that drives the drum 250 and the pulsator 260. The drum is installed at a lower side of the tub 200. The pulsator 260 is installed in the drum 250. Rotation of the pulsator produces a water flow in the drum 250. That is, the dissolving unit 300 is disposed closer to the lower side of the tub 200 than the upper opening of the tub 200. In this configuration, the dissolving unit 300 may be installed without requiring a separate installation space and without interference with the tub 200 when the tub 200 is supported by the housing 100 by a suspension system.

The washing machine 101 according to the exemplary embodiment of the present disclosure includes the housing 100, the tub 200, the drum 250, the water supply unit 130, the dissolving unit 300, the bubble generating unit 400, the drain valve 900, and the control unit 700.

The water supply unit 130 supplies washing water for washing laundry. As an example, the water supply unit 130 may supply washing water separately to the tub 200 and the dissolving unit 300.

The dissolving unit 300 can contain air and receive water from the water supply unit 130, and allow the air to be dissolved in the water. More specifically, air stored in the dissolving unit 300 can be mixed with the water supplied from the water supply unit 130 while the water flows inside the dissolving unit 300.

The bubble generating unit 400 is installed in the housing 100. The bubble generating unit 400 can generate bubbles by using the water/air mixture introduced from the dissolving unit 300 and advantageously supply the bubbles into the tub 200. Therefore, the water supplied into the tub 200 may include bubbles supplied from the bubble generating unit 400.

The drain valve 900 is installed in the dissolving unit 300 and may discharge water/air mixture remaining in the dissolving unit 300 to the outside, e.g., through the drain line 210. The drain valve 900 is controlled by the control unit 700.

Based on a preset washing process, the control unit 700 determines if adequate washing water and bubbles have been supplied into the tub 200. If yes, the control unit 700 ceases supplying the bubbles into the tub 200. More specifically, the control unit 700 controls the water supply unit 130 to stop the supply of water to the dissolving unit 300. The control unit 700 opens the drain valve 900 to discharge the water or water/air mixture remaining in the dissolving unit 300.

Therefore, the control unit 700 may effectively prevent the interior of the dissolving unit 300 from being contaminated or the dissolving unit 300 from being frozen e.g., during the winter, which would occur if water remains in the dissolving unit 300 for extended time.

When the control unit 700 of the washing machine 101 determines that the water/air mixture in the dissolving unit 300 has been completely discharged from the dissolving unit 300, the control unit 700 may close the drain valve 900.

Based on the preset time or based on the amount of water/air mixture remaining in the dissolving unit 300 as detected by a detection means (such as the water level sensor disposed in the dissolving unit 300), the control unit 700 may determine whether the water/air mixture has been completely discharged. If yes, the control unit 700 may close the drain valve 900.

With the aforementioned configuration, the washing machine 101 may effectively prevent the dissolving unit 300 from damage that could be caused if the residual water in the dissolving unit 300 freezes during cold weather.

Hereinafter, an exemplary operational process of the washing machine 101 according to an embodiment of the present disclosure is described with reference to FIGS. 1 to 5.

As illustrated in FIGS. 1 and 2, the washing machine 101 includes: the tub 200 which stores washing water; the drain line 210 which is installed at the lower side of the tub 200 and may discharge washing water stored in the tub 200 to the outside; and a supply nozzle 220 which may supply washing water into the tub 200.

Water is supplied into the dissolving unit 300 by the water supply unit through the dissolving inlet port 331 of the dissolving unit 300. Water supplied into the dissolving unit 300 flows inside the dissolving unit 300 and dissolves air stored in the dissolving unit 300. More specifically, water is introduced into the inner body 320 through the dissolving inlet port 331, and contained in the inner body 320. Water can flow along the inner wall of the inner body 320, and overflow toward the dissolving flow path formed between the inner circumferential surface of the outer body 310 and the outer circumferential surface of the inner body 320 through the porous portion 321 on the inner body 320. The porous portion is adjacent to the opening of the inner body 320.

Therefore, water introduced into the dissolving unit 300 can flow into the inner body 320 and along the dissolving flow path, and can be effectively mixed with air in the dissolving unit 300 without requiring a separate pump or agitating device, thereby allowing air to be dissolved in the water.

Water overflowing to the dissolving flow path can dissolve air stored in the dissolving unit 300. Water/air mixture may be supplied into the bubble generating unit 400 through the dissolving guide port 311.

The air in the water/air mixture supplied through the bubble inlet port 411 can be separated from the mixture while the water/air mixture passes through the bubble flow path 421 of the bubble nozzle 420, thereby generating bubbles (micro bubbles). Bubbles may be discharged to the outside of the bubble generating unit 400 through the bubble discharge port 412, and then supplied into the tub 200 through the supply nozzle 220.

Bubbles supplied into the tub 200 can advantageously reduce surface tension between the laundry and detergent or foreign substances adherent to the laundry, thereby allowing the laundry to be effectively cleaned.

The water level sensor 190 can detect a level of the water in the dissolving unit 300, and transmit the information to the control unit 700. According to the level of the water in the dissolving unit 300 as detected by the water level sensor 190, the control unit 700 may control the operations of the water supply unit 130 and the drain valve 900.

When the information detected by the water level sensor 190 is equal to or higher than the preset first water level information value, the control unit 700 may decide that the interior of the dissolving unit 300 needs to be refilled with air. In this case, the control unit 700 allows the water supply unit 130 to stop the supply of the water into the dissolving unit 300. The control unit 700 can open the drain valve 900 so that water stored in the dissolving unit 300 is discharged to the drain line 210 through the dissolving drain port 312.

That is, when the information detected by the water level sensor 190 is equal to or greater than the preset first water level information value, the control unit 700 treats this as an indication that that the bubble generating unit 400 cannot effectively generate bubbles given the amount of air remaining in the dissolving unit 300, and accordingly the control unit 700 may open the drain valve 900 to drain the water out of the dissolving unit 300.

When the information detected by the water level sensor 190 is lower than the preset first water level information value, the control unit 700 treats this information as an indication that the air remaining in the dissolving unit 300 may be dissolved in the water supplied from the water supply unit 130 and the bubble generating unit 400 may effectively generate bubbles.

Water remaining in the dissolving unit 300 can be discharged to the drain line 210 through the dissolving drain port 312 by the drain valve 900 which is controlled by the control unit 700. As the level of the water in the dissolving unit 300 decreases, the air pressure in the dissolving unit 300 decreases. As a result, the air supply check valve 340 can be opened to allow the outside air to enter the dissolving unit 300.

As the air supply check valve 340 is opened, the increased air pressure in the dissolving unit 300 may allow the water to be more effectively discharged to the dissolving drain port 312.

Based on a preset time, or based on a detection by the water level sensor 190 that a water level is lower than the second water level information value, the control unit 700 may determine that all the water remaining in the dissolving unit 300 has been discharged through the dissolving drain port 312. In this situation, the control unit 700 closes the drain valve 900.

When air pressure in the dissolving unit 300 is at or above a predetermined pressure, the air supply check valve 340 is closed, thereby preventing air from being introduced into the dissolving unit 300.

Thereafter, the control unit 700 may instruct the water supply unit 130 to restart supplying water into the dissolving unit 300.

With the aforementioned configuration, the washing machine 101 according to the exemplary embodiment of the present disclosure can generate bubbles and use the bubbles to effectively remove foreign substances or residual detergent adherent to the laundry when washing or rinsing the laundry.

While the exemplary embodiments of the present disclosure have been described with reference to the accompanying drawings, those skilled in the art will understand that the present disclosure may be implemented in any other specific form without changing the technical spirit or an essential feature thereof.

Accordingly, it should be understood that the aforementioned exemplary embodiments are described for illustration in all aspects and is not limiting, and the scope of the present disclosure shall be represented by the claims to be described below, and it should be construed that all of the changes or modified forms induced from the meaning and the scope of the claims, and an equivalent concept thereto are included in the scope of the present disclosure.

From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the scope and spirit being indicated by the following claims. 

What is claimed is:
 1. A washing machine comprising: a dissolving unit configured to: contain air and water; and produce a water/air mixture; a water supply unit configured to supply water to the dissolving unit; a bubble generating unit coupled to the dissolving unit and configured to generate bubbles by using the water/air mixture supplied from the dissolving unit; a drain valve disposed in the dissolving unit and configured to discharge the water/air mixture out from the dissolving unit; and a control unit configured to control a supply of the water/air mixture to the bubble generating unit by controlling the water supply unit and the drain valve.
 2. The washing machine of claim 1, further comprising a water level sensor disposed in the dissolving unit and configured to: detect a water level in the dissolving unit, and provide detected information to the control unit.
 3. The washing machine of claim 2, wherein, responsive to a detection that the water level is equal to or higher than a preset first water level information value, the control unit is configured to stop a supply of water from the water supply unit; and open the drain valve.
 4. The washing machine of claim 3, wherein, responsive to a detection that the water level is lower than a preset second water level information value after the drain valve is opened, the control unit is configured to close the drain valve.
 5. The washing machine of claim 3, wherein the control unit is configured to close the drain valve when a preset time has elapsed after the drain valve has been opened.
 6. The washing machine of claim 1, wherein the dissolving unit comprises: an outer body that is hollow and comprises a first side that is open; and an inner body that is hollow and comprises a first side that is open, wherein the inner body is disposed in the outer body, wherein a gap between the inner body and the outer body forms a dissolving flow path.
 7. The washing machine of claim 6, wherein the dissolving unit further comprises a dissolving cap coupled to the first side of the outer body, wherein the dissolving cap comprises a dissolving inlet port configured to allow water to be supplied into the inner body.
 8. The washing machine of claim 7, wherein the inner body comprises a porous portion configured to allow water to overflow from the inner body to the dissolving flow path.
 9. The washing machine of claim 7, wherein the dissolving unit further comprises a dissolving guide port disposed on the outer body and configured to guide water passing through the dissolving flow path to flow to the bubble generating unit.
 10. The washing machine of claim 9, wherein the dissolving unit further comprises a dissolving drain port disposed on the outer body and spaced apart from the dissolving guide port, wherein the drain valve is installed on the dissolving drain port.
 11. The washing machine of claim 10, wherein the dissolving unit further comprises an inner hole formed at a second side of the inner body and configured to communicate with the dissolving flow path.
 12. The washing machine of claim 10, wherein the dissolving unit further comprises an air supply check valve installed in the dissolving cap and configured to allow air to enter the outer body and the inner body when water is discharged through the dissolving drain port.
 13. The washing machine of claim 1, further comprising: a housing; a tub enclosed by the housing and configured to receive bubbles generated by the bubble generating unit; and a drum disposed in the tub and configured to accommodate laundry.
 14. The washing machine of claim 13, wherein the dissolving unit is disposed between the housing and the tub at a location closer to a lower side of the tub than an upper side of the tub.
 15. A washing machine comprising: a housing; a tub disposed inside the housing; a dissolving unit configured to: contain air and water; and produce a water/air mixture; a water supply unit configured to supply water to the dissolving unit; a bubble generating unit coupled to the dissolving unit and configured to generate bubbles by using the water/air mixture supplied from the dissolving unit; a drain valve disposed in the dissolving unit and configured to discharge the water/air mixture out of the dissolving unit; and a control unit configured to control a supply of the water/air mixture to the bubble generating unit by controlling the water supply unit and the drain valve, wherein the control unit is configured to: stop a supply of water to the dissolving unit by controlling the water supply unit; and open the drain valve to discharge the water/air mixture from the dissolving unit when the bubbles are not supplied to the tub.
 16. The washing machine of claim 15, wherein when the control unit is configured to: determine that the water/air mixture in the dissolving unit has been substantially discharged; and close the drain valve.
 17. The washing machine of claim 15, wherein the dissolving unit comprises: an outer body that is hollow and comprises an open end; and an inner body that is hollow and comprises an open end, wherein the inner body is disposed in the outer body, wherein a gap between the inner body and the outer body forms a dissolving flow path.
 18. The washing machine of claim 15, wherein control unit is configured to close the drain valve when a preset time has elapsed after the drain valve has been opened.
 19. The washing machine of claim 15, wherein the bubble generating unit comprises a pressure reduction region. 